880348-51-6Relevant academic research and scientific papers
Novel multi-dentate phosphines for Pd-catalyzed alkoxycarbonylation of alkynes promoted by H2O additive
Yang, Da,Liu, Lei,Wang, Dong-Liang,Lu, Yong,Zhao, Xiao-Li,Liu, Ye
, p. 236 - 244 (2019/02/19)
A series of novel multi (bi-/tri-/tetra-)-dentate phosphines with good robustness against water and oxygen were synthesized and fully characterized. It was found that the developed ionic tri-dentate phosphine (L2′) enabled Pd-catalyzed alkoxycarbonylation of alkynes most efficiently while H2O was used as an additive instead of acid. As for L2′, its unique steric configuration with two types of potential P-P chelation modes (P?P distance of 4.31 ? and 4.36 ? respectively) to Pd-centre rendered the corresponding Pd-catalyst high activity and good stability for alkoxycarbonylation of alkynes. The in situ FT-IR analysis also verified that the formation and stability of Pd–H active species were greatly facilitated with the presence of L2′ as well as H2O additive. In addition, as an ionic phosphine, L2′ based PdCl2(MeCN)2 system immobilized in RTIL of [Bmim]NTf2 could be recycled for 7 runs without obvious activity loss or metal leaching.
Stabilization of Organic Materials
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, (2008/12/04)
The invention describes a process for stabilizing an organic material against oxidative, thermal or light-induced degradation, which comprises incorporating therein or applying thereto at least a compound of the formula (I) wherein the general symbols are
